This invention relates to manifolds and more particularly to manifolds formed generally of non-metallic materials.
Manifolds traditionally have been formed of steel or other metal materials. Whereas steel manifolds have proved to be generally satisfactory in most applications, they tend to be relatively expensive both because of the expensive nature of the material involved and the expensive nature of the operations required to form the metal manifold. Metal manifolds are also subject to corrosion, particularly when used in a liquid environment. Attempts have been made in the past to use less expensive materials in place of the relatively expensive steels traditionally used. For example, manifolds have been formed of various types of plastic and fibrous materials. Whereas these non-metallic manifolds have offered a price advantage as compared to steel manifolds, they have often proven to be not as serviceable or as durable as the steel manifolds and, in particular, have not been capable of sustaining the required torque loads at the various interconnections to the manifold over extended periods of usage.